Positive electrode active material and preparation method therefor, positive electrode plate, secondary battery, battery module, battery pack, and power consuming device

1 . A positive electrode active material including a compound represented by formula (I),

Li a A x Mn 1-y B y P 1-z C z O 4-n D n    (I)

wherein:

the A includes one or more elements selected from group IA, group IIA, group IIIA, group IIB, group VB, and group VIB;

the B includes one or more elements selected from group IA, group IIA, group IIIA, group IVA, group VA, group IIB, group IVB, group VB, group VIB, and group VIII;

the C includes one or more elements selected from group IIIA, group IVA, group VA, and group VIA;

the D includes one or more elements selected from group VIA and group VIIA;

the a is selected from a range of 0.85 to 1.15;

the x is selected from a range of 0 to 0.1;

the y is selected from a range of 0.001 to 0.999;

the z is selected from a range of 0 to 0.5; and

the n is selected from a range of 0 to 0.5.

2 . The positive electrode active material according to claim 1 , wherein:

the A includes one or more elements selected from Rb, Cs, Be, Ca, Sr, Ba, Ga, In, Cd, V, Ta, Cr, Zn, Al, Na, K, Mg, Nb, Mo, and W; and/or

the B includes one or more elements selected from Rb, Cs, Be, Ca, Sr, Ba, In, Pb, Bi, Cd, Hf, Ta, Cr, Ru, Rh, Pd, Os, Ir, Pt, Zn, Al, Na, K, Mg, Mo, W, Ti, V, Zr, Fe, Ni, Co, Ga, Sn, Sb, Nb, and Ge; and/or

the C includes one or more elements selected from B (boron), S, Si, and N; and/or

the D includes one or more elements selected from S, F, Cl, and Br.

3 . The positive electrode active material according to claim 1 , wherein:

the A includes any element selected from Zn, Al, Na, K, Mg, Nb, Mo, and W; and/or

the B includes one or more elements selected from Ti, V, Zr, Fe, Ni, Mg, Co, Ga, Sn, Sb, Nb, and Ge; and/or

the C includes any element selected from B (boron), S, Si, and N; and/or

the D includes any element selected from S, F, Cl, and Br.

4 . The positive electrode active material according to claim 1 , wherein:

the a is selected from a range of 0.9 to 1.1; and/or

the x is selected from a range of 0.001 to 0.005; and/or

the y is selected from a range of 0.001 to 0.5; and/or

the z is selected from a range of 0.001 to 0.5; and/or

then is selected from a range of 0 to 0.1.

5 . The positive electrode active material according to claim 1 , wherein:

the x is 0, the z is selected from a range of 0.001 to 0.5, and the n is selected from a range of 0.001 to 0.1; or

the x is selected from a range of 0.001 to 0.1, the z is 0, and then is selected from a range of 0.001 to 0.1; or

the x is selected from a range of 0.001 to 0.1, the z is selected from a range of 0.001 to 0.5, and the n is 0; or

the x is 0, the z is 0, and then is selected from a range of 0.001 to 0.1; or

the x is 0, the z is selected from a range of 0.001 to 0.5, and the n is 0; or

the x is selected from a range of 0.001 to 0.1, the z is selected from a range of 0.001 to 0.5, and then is selected from a range of 0.001 to 0.1.

6 . The positive electrode active material according to claim 1 , wherein y:z is selected from a range of 0.002 to 999.

7 . The positive electrode active material according to claim 1 , wherein z: n is selected from a range of 0.002 to 500.

8 . The positive electrode active material according to claim 1 , wherein:

the A includes one or more elements selected from Zn, Al, Na, K, Mg, Nb, Mo, and W;

the B includes one or more elements selected from Ti, V, Zr, Fe, Ni, Mg, Co, Ga, Sn, Sb, Nb, and Ge;

the C includes one or more elements selected from B (boron), S, Si, and N;

the D includes one or more elements selected from S, F, Cl, and Br;

the a is selected from a range of 0.9 to 1.1, the x is selected from a range of 0.001 to 0.1, the y is selected from a range of 0.001 to 0.5, the z is selected from a range of 0.001 to 0.1, and the n is selected from a range of 0.001 to 0.1.

9 . The positive electrode active material according to claim 1 , wherein:

the B includes one or more elements selected from Zn, Al, Na, K, Mg, Mo, W, Ti, V, Zr, Fe, Ni, Co, Ga, Sn, Sb, Nb, and Ge;

the C is one or more elements selected from B, Si, N, and S;

the a is selected from a range of 0.9 to 1.1, the x is 0, the y is selected from a range of 0.001 to 0.5, the z is selected from a range of 0.001 to 0.1, and then is 0.

10 . The positive electrode active material according to claim 1 , wherein:

the positive electrode active material includes an inner core and a shell coating the inner core;

the inner core includes the compound represented by formula (I); and

the shell includes one or more coating layers, and the coating layer has ion conductivity or electron conductivity.

11 . The positive electrode active material according to claim 10 , wherein each of the one or more coating layers independently includes one or more selected from pyrophosphate, phosphate, carbon, doped carbon, an oxide, a boride, and a polymer.

12 . The positive electrode active material according to claim 11 ,

wherein:

the pyrophosphate is M b (P 2 O 7 ) c ; and/or

the phosphate is X m (PO 4 ) q ; and/or

doping elements in the doped carbon include one or more elements selected from group IIIA, group VA, group VIA, and group VIIA; and/or

the oxide is M′ d O e ; and/or

the boride is Z v B w ; and/or

the polymer includes one or more selected from polysaccharides and their derivatives, and polysiloxanes;

wherein:

the M, X, and Z each independently include one or more elements selected from group IA, group IIA, group IIIA, group IB, group IIB, group IVB, group VB, group VIIB, and group VIII;

the b is selected from a range of 1 to 4;

the c is selected from a range of 1 to 6;

the m is selected from a range of 1 to 2;

the q is selected from a range of 1 to 4;

the M′ includes one or more elements selected from alkali metals, alkaline earth metals, transition metals, group IIIA elements, group IVA elements, lanthanides, and Sb;

the d is greater than 0 and less than or equal to 2;

the e is greater than 0 and less than or equal to 5;

the v is selected from a range of 1 to 7; and

the w is selected from a range of 1 to 2.

13 . The positive electrode active material according to claim 12 , wherein:

the M, X, and Z each independently include one or more elements selected from Li, Fe, Ni, Mg, Co, Cu, Zn, Ti, Ag, Zr, Nb, Mn, and Al; and/or

the doping elements in the doped carbon include one or more selected from nitrogen, phosphorus, sulfur, boron, and fluorine; and/or

the M′ includes one or more elements selected from Li, Be, B, Na, Mg, Al, Si, P, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Te, W, La, and Ce; and/or

the polysiloxane is selected from one or more of polysiloxanes with a linear structure and polysiloxanes with a ring structure; and/or

the polysaccharide is selected from one or more of plant polysaccharides and marine polysaccharides.

14 . The positive electrode active material according to claim 10 , wherein the shell includes a coating layer.

15 . The positive electrode active material according to claim 10 , wherein the shell includes a first coating layer coating the inner core and a second coating layer coating the first coating layer.

16 . The positive electrode active material according to claim 15 , wherein the first coating layer includes one or more selected from pyrophosphate, phosphate, an oxide, and a boride, and the second coating layer includes one or more selected from carbon and doped carbon.

17 . The positive electrode active material according to claim 10 , wherein the shell includes a first coating layer coating the inner core, a second coating layer coating the first coating layer, and a third coating layer coating the second coating layer.

18 . The positive electrode active material according to claim 15 , wherein the first coating layer includes pyrophosphate, and the second coating layer includes one or more of selected from phosphate, an oxide, and a boride, and the third coating layer includes one or more selected from carbon and doped carbon.

19 . The positive electrode active material according to claim 10 , wherein:

the positive electrode active material includes an inner core and a shell coating the inner core;

the inner core includes Li a Mn 1-y B y P 1-z C z O 4 , wherein the a is selected from a range of 0.9 to 1.1, the y is selected from a range of 0.001 to 0.5, and the z is selected from a range of 0.001 to 0.1, the B includes one or more elements selected from Ti, V, Zr, Fe, Ni, Mg, Co, Ga, Sn, Sb, Nb, and Ge, and the C includes one or more elements selected from B (boron), S, Si, and N; and

the shell includes a first coating layer coating the inner core and a second coating layer coating the first coating layer, wherein:

the first coating layer includes pyrophosphate of MP 2 O 7 and phosphate of XPO 4 ;

the M and X are each independently selected from one or more of Li, Fe, Ni, Mg, Co, Cu, Zn, Ti, Ag, Zr, Nb, and Al; and

the second coating layer includes carbon.

20 . The positive electrode active material according to claim 10 , wherein:

the positive electrode active material includes an inner core and a shell coating the inner core;

the inner core includes Li a Mn 1-y B y P 1-z C z O 4 , wherein the a is selected from a range of 0.9 to 1.1, the y is selected from a range of 0.001 to 0.5, and the z is selected from a range of 0.001 to 0.1, the B includes one or more elements selected from Ti, V, Zr, Fe, Ni, Mg, Co, Ga, Sn, Sb, Nb, and Ge, and the C includes one or more elements selected from B (boron), S, Si, and N; and

the shell includes a first coating layer coating the inner core, a second coating layer coating the first coating layer, and a third coating layer coating the second coating layer, wherein

the first coating layer includes pyrophosphate of Li f QP 2 O 7 and/or Q g (P 2 O 7 ) h , wherein, 0≤f≤2, 1≤g≤4, 1≤h≤6, the Q in the pyrophosphate of Li f QP 2 O 7 and/or the Q in Q g (P 2 O 7 ) h are each independently one or more elements selected from Fe, Ni, Mg, Co, Cu, Zn, Ti, Ag, Zr, Nb, and Al;

the second coating layer includes crystalline phosphate of XPO 4 , wherein X is one or more elements selected from Li, Fe, Ni, Mg, Co, Cu, Zn, Ti, Ag, Zr, Nb, and Al; and

the third coating layer includes carbon.